Sandpapering machine



Feb. 16, 1943 T. N

SANDPAPERING MACHINE 2 Sheets-Sheet 1 Filed March 26, 1942 InventorJa'bipk 2 1120272 1 Feb. 16, 1943. A. T; MUNN 2,311,346

SANDPAPERING MACHINE Filed March 26, 1942 2 Sheets-Sheet 2 Patented Feb.16, 1943 OFFICE SANDPAPERING MACHINE Adolph T. Munn, Pageland, S. C.Application March 26, 1942, Serial No. 436,348

3 Claims.

My invention'relates to improvements in sandpapering machines for use indressing down boards or planks. a

The invention is designed with the particular object in view ofproviding a simply constructed machine equipped for quickly and evenlysandpapering boards, or planks, of different gauge and which iseconomical to operate, install and service.

To the accomplishment of the above, and. subordinate objects presentlyappearing, a preferred embodiment of my invention has been illustratedin the accompanying drawings, set forth in detail in the succeedingdescription, and defined in the claims appended hereto.

In said drawings: a

Fig. 1 is a view in side elevation of a sandpapering machine embodyingmy improvements,

Figure 2 is a View in top plan, partly broken away,

Figure 3 is a fragmentary view in longitudinal vertical section, takenon the line 33 of Figure 2, and drawn to an enlarged scale, Figure 4 isa view in transverse section, taken on the line 44 of Figure 1, anddrawn to an enlarged scale, and

Figure 5 is a similar view, taken on the line 5-5 of Figure l.

Referring to the drawings by numerals, my improved sandpapering machinecomprises an elongated, rectangular bed I, of any suitable material,supported by side and end frame members 2, 3 forming a'rectangular framebeneath said bed I and which is in turn supported by corner legs 4.

Adjacent the transverse center of the bed I and also one end thereof arepairs of lower and upper transverse rollers 5, 6 for feeding boards orplanks endwise therebetween longitudinally of the bed I. means presentlydescribed, and fastupon transverse shafts I journaled at their ends inbearing brackets 8 depending from the side members 2. The upper rollers6 are idling pressure members fast upon shafts forming end trunnions 9on said rollers and which are rotatable and vertically movable invertically grooved bearing brackets H ari ing from opposite sides of thebed I and connected in pairs by upper transverse bars l2. Tension meansis provided for each upper roller 6 for urging the same downwardly andcomprising a hand screw l3 threaded downwardly through the bar 12 abovethe roller 6 for turning against an upwardly bowed leaf spring l4 havingits ends projecting into the grooves of the bearing brack- The lowerrollers 5 are driven, by

ets H and resting upon blocks l5 vertically slidable in said grooves andseated on the trunnions 9 of said roller 6.

Intermediate the described pairs of rollers 5, 6 and surmounting the bedI is a substantially rectangular sanding head 16 of flat form mounted,by means presently described, for reciprocation longitudinally of saidbed with its sides parallel with the sides of said bed I. The mountingfor the sanding head llicomprises a carriage including a pair of siderails I'l extending lengthwise along the outer sides of the members 2and provided with longitudinally extending guides I8 slidable insuitable guideways l9 extending longitudinally along the outer sides ofthe members 2. A cross-bar 20 extending beneath the members 2 connectsthe rails I! in the transverse center thereof. A pair of forked ears 2!arise from each rail 11 adjacent the ends thereof, respectively, andwhich accommodate therein studs 22 extending laterally from the sides ofthe sanding head l6, whereby said head is coupled to the rails l1 andvertically movable relative thereto. Cotter pin 23 may be provided inthe outer ends of the studs 22 for a purpose which will be apparent.

Tension means for exerting downward pressure on the sanding head I6 isprovided as follows: Spanning the sanding head It in the transversecenter thereof is a bar-like yoke of inverted U form having a verticalside leg 24 pivoted, as at, 25, to an upright 26 on the beforementioned.bar 20, and an opposite side leg- 21 adapted to rest on an upright 28arising from the other end of the bar 20. A suitable latch is providedfor securing the leg 21 to the upright 28. A hand screw 30 extendsthrough the centerlof the described yoke in upright position. Anupwardly arched spider 3|, is secured, as at am, to the top of thesanding block l6, saidspider have ing an apertured hub 32 slidable onthe lower end of the hand screw 30 and retained on thefhand screw bymeans of a cotter pin 33 passing through the lower end of said handscrew. A coil spring 34 sleeved onto the hand screw 30 between said hub32 and a collar 35 on said screw tends to urge the spider 3!, and hencethe sanding head l6, downwardly.

The sanding head I6 is designed to carry a sheet of sandpaper, or thelike, 36 stretched across the bottom face of the head with edges turnedup alongside the transverse edges of said head. For securing the sheetof sandpaper 36 to the head, a pair of resilient bowed clamping bails 31are provided to extend alongside said transverse edges of the sandinghead to clamp the upturned edges of the sheet to the head, said bails 31being pivoted, as at 38, to the sides of the head for vertical swingingto releasing position.

Driving means for reciprocating the described carriage and sanding headis provided and will now be described in detail. Adjacent one end of thebed I an electric motor 39 is suitably suspended from one of the members2 and provided with a belt pulley 40 on the armature shaft 4| thereofwhich is connected by a belt 42 to a relatively larger pulley wheel 43fast on one end of a transverse shaft 44 suitably journaled at its endson the members 2. The pulley wheel 43 is provided with a crank pin 45coacting with a vertically slotted head 46 on one end of a slidebar 47,the other end of which is fastened, as at 48, to one of the rails II.The slide bar 41 is suitably guided for endwise movement in bearings, asat 48, provided on one of the side members 2. Obviously, as the pulleywheel 43 is rotated, the slide bar 41 will be reciprocated and similarmotion imparted to the sanding head l6 through the medium of thedescribed carriage therefor. Any suitable means may be provided forcontrolling the motor 39.

Coming now to the drive for the lower rollers 5, extending along onemember 2 is a worm shaft 49 suitably journaled in bearing brackets 50depending from said member and provided with worm sections 5| meshingwith a pair of worm wheels 52 fast on the before mentioned shafts 1,respectively. A jack shaft 53 operatively connected to the worm shaft 49by bevel gearing 54 and suitably journaled in fixed bearings 55 opcratessaid worm shaft 49. Intermediate the shaft 44 and jack shaft 53 is asuitably mounted reverse gearing including a worm wheel 59, a pair ofworm shafts 5'! upon opposite sides of said wheel 56, and adapted todrive the same in opposite directions, respectively, a shaft 58 drivenfrom the worm wheel 56 by bevel gearing 59 and operatively connected tothe jack shaft 53 by bevel gearing 60; and a twin bevel gear unit 6|splined on the shaft 44 for shifting in opposite directions into meshwith bevel gears 62 on the worm shafts '51, respectively. A suitableshifter 62 operative by a slide rod 63 is provided for shifting the unit6|.

The operation of the described machine will be readily understood. Aboard, or plank, 64 to be sandpapered is inserted between the rollers 5,6 of either pair and underneath the sanding head I6 to be fed along thebed I in eitherdirection by said rollers according to the direction ofthe drive of said rollers as determined by a setting of the describedreverse gearing. As the board is fed, the sanding head [6 isreciprocated over the same, as will be clear. As the sandpaperingoperation progresses along the board, it is fed in between the next pairof rollers 5, ,6 to be fed by said rollersalso. By unlatching thedescribed yoke and swinging the same upwardly on the hinge 25, accessmay be had to the sanding head I6 to replace the sheet of sandpaper 36when the latter becomes worn.

As will be understood from an inspection of Figure 3, the rollers 5extend into transverse slots 65 in the bed I to engage the under side ofthe board, or plank,*64.

The foregoing will, it is believed, sufiice to impart a clearunderstanding of my invention without further explanation.

Manifestly, the invention, as described, is susceptible of modificationwithout departing from the inventive concept, and right is hereinreserved to such modifications as fall within the scope of the subjoinedclaims.

What is claimed is:

1. A board and plank sanding machine of the class described, comprisinga bed upon which the work is adapted to be placed for sanding purposes,means on said bed for frictionally engaging and feeding and guiding thework, a carriage structure mounted for reciprocation on said bed, saidcarriage comprising parallelslidably mounted rails with upstandingnotched lugs, a sandpaper block cradled in said lugs, a yoke carried byS id rails and spannin said block, and spring tensioning means on theyoke cooperating with the block, together with operating means for saidcarriage.

2. In a sanding machine, a bed, a reciprocating carriage'on the bedcomprising a pair of parallel side rails having upstanding notched lugs,a sanding block having members fitting in said notches to support theblock on said rails, means on said block for detachably attaching sheetsof sandpaper thereto, and means to exert tension downwardly against saidblock comprising a yoke upstanding from said rails in straddlingrelation to the block and bed and having a top bar, a hand screwdepending through said bar, a spider on said block in which one end ofthe screw is rotatably and slidably mounted, and spring means urging thespider downwardly of said screw.

3. In a sanding machine, a bed, a reciprocating carriage on the bedcomprising a pairof parallel side rails having upstanding notched lugs,a sanding block having members fitting in said notches to support theblock on said rails, means on said block fordetachably attachingsheetsof sandpaper thereto, and means to exert tension downwardlyagainst said block comprising a yoke upstanding from said rails instraddling relation to the block and bed and having a top bar, a handscrew depending through said bar, a spider on said block in which oneend of the screw is rotatably and slidably mounted, and spring meansurging the spider downwardly of said screw, said yoke being hinged toone of said rails to be swung laterally clear of the bed, and saidblock, screw and spider being inseparable for swinging of the same withsaid yoke.

ADOLPH T. 'MUNN.

